Circuit Description
Ignition voltage is supplied to terminal C2 of the Electronic Brake Control Relay. The above condition enables the EBCM/EBTCM to energize the pullin coil by completing the ground circuit at connector C1 terminal A11 of the EBCM/EBTCM. The magnetic field created closes the Electronic Brake Control Relay contacts. The magnetic field also allows battery voltage and current through the Electronic Brake Control Relay terminal C1 to be supplied to the EBCM/EBTCM through connector C2 terminal C and to the Brake Solenoid Valves through S279.
Conditions for Setting the DTC
DTC 1216 can set anytime.
DTC C1216 detects an open in the Electronic Brake Control Relay coil circuit. An open in the above circuit will not allow the Electronic Brake Control Relay to energize. If the Electronic Brake Control Relay cannot energize voltage/current fails to reach the motors and solenoids.
DTC C1216 sets alone if the above malfunction exists and the ignition is turned off before reaching 5 km/h (3 mph).
Action Taken When the DTC Sets
| • | A malfunction DTC stores. |
| • | The ABS/TCS disables. |
| • | The amber ABS/TCS warning indicators turns on. |
| • | The red BRAKE warning indicator turns on if the rear piston in the ABS brake motor pack is not in the home position. |
Conditions for Clearing the DTC
| • | The condition responsible for setting the DTC no longer exists and the Scan Tool Clear DTC function is used. |
| • | 100 drive cycles pass with no DTC detected. |
Diagnostic Aids
The following conditions may cause an intermittent malfunction:
| • | A poor connection |
| • | Rubbed-through wire insulation |
| • | A broken wire inside the insulation |
Use the enhanced diagnostic function of the Scan Tool in order to measure the frequency of the malfunction. Refer to the Scan Tool manual or J 39200 located in this section for the procedure.
If the frequency of the malfunction is high, but is currently intermittent inspect for high coil resistance. Use a J 39200 in order to measure for high coil resistance by measuring between Electronic Brake Control Relay terminal 85 and terminal 86. If the resistance shows greater than 95 ohms replace the Electronic Brake Control Relay.
Thoroughly inspect any circuitry that may be causing the intermittent complaint for the following conditions:
| • | Backed out terminals |
| • | Improper mating |
| • | Broken locks |
| • | Improperly formed or damaged terminals |
| • | Poor terminal-to-wiring connections |
| • | Physical damage to the wiring harness |
Clear the DTCs after completing the diagnosis. Test drive the vehicle for three drive cycles in order to verify that the DTC does not reset. Use the following procedure in order to complete one drive cycle:
- Start the vehicle.
- Drive the vehicle over 16 km/h (10 mph).
- Stop the vehicle.
- Turn the ignition to the OFF position.
Important: Zero the J 39200 test leads before making any resistance measurements.
Step | Action | Value(s) | Yes | No | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1 | Was the Diagnostic System Check performed? | -- | Go to Step 2 | Go to Diagnostic System Check | ||||||||||
2 |
Does the Scan Tool indicate that the electronic brake control relay is ON and that the voltage is equal to or greater than the specified voltage? | 10V | Go to Step 12 | Go to Step 3 | ||||||||||
3 |
Is the voltage equal to or greater than the specified voltage? | 10V | Go to Step 4 | Go to Step 13 | ||||||||||
4 |
Is the resistance within the specified range? | 0-95ohms | Go to Step 6 | Go to Step 5. | ||||||||||
5 | Replace the electronic brake control relay. Is the repair complete? | -- | Go to Diagnostic System Check | -- | ||||||||||
6 |
Is the resistance within the specified range? | 0-2ohms | Go to Step 8 | Go to Step 7 | ||||||||||
7 | Repair the open or high resistance in CKT 1632. Is the repair complete? | -- | Go to Diagnostic System Check | -- | ||||||||||
8 |
Are there signs of poor terminal contact, corrosion, or damaged terminals? | -- | Go to Step 9 | Go to Step 10 | ||||||||||
9 |
Is the repair complete? | -- | Go to Diagnostic System Check | -- | ||||||||||
10 |
Does DTC C1216 set as current DTC? | -- | Go to Step 11 | Go to Step 12 | ||||||||||
11 | Replace the EBCM/EBTCM. Is the repair complete? | -- | Go to Diagnostic System Check | -- | ||||||||||
12 | The system is functioning properly at this time. The malfunction may be intermittent or is not present at the time of testing. Is a concern still present? | -- | Go to Diagnostic Aids | Go to Diagnostic System Check | ||||||||||
13 |
Is the voltage equal to or greater than the specified value? | 10V | Go to Step 15 | Go to Step 14 | ||||||||||
14 | Repair the open or high resistance in the following circuits and components:
Refer to Power Distribution Schematics in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check | -- | ||||||||||
15 | Use the J 39200 in order to measure the resistance between the ABS/TCS IGN fuse (10A) terminals. Is the resistance within the specified range? | 0-2ohms | Go to Step 16 | Go to Step 17 | ||||||||||
16 | Repair the open or high resistance in CKT 1639. Is the repair complete? | -- | Go to Diagnostic System Check | -- | ||||||||||
17 | Repair the short to ground in CKT 1639. Is the repair complete? | -- | Go to Diagnostic System Check | -- |
